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  <element name="EffectiveIncomeTaxRateReconciliationTaxRefundsRelatedToResearchAndDevelopment" id="zfgn_EffectiveIncomeTaxRateReconciliationTaxRefundsRelatedToResearchAndDevelopment" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="FollowOnOfferingMember" id="zfgn_FollowOnOfferingMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncreaseDecreaseInTaxIncentivesReceivable" id="zfgn_IncreaseDecreaseInTaxIncentivesReceivable" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
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</schema>





